Took some MS paint liberties. I was thinking if you filed an agressive arc to the blue line at the top of your 'spike' it could match the 'fins' you have at the back of the marker. As well, I'd arc the inner section like I've shown with the purple line... then again.. I like spiky/curvy markers..

As for the bolt alignment thing, I haven't had a problem, besides, it's not like the entire bolt is popping out of the gun when it recocks.

thats pretty sick.. i was thinking of either finding someone to halfback my imagine.. or sending my agressor out to alamo city paintball to have them make it a top cocking gun.. (i would do the work myself but i dont have a dremmel, ive never used one, and i dont think i have the patience..)

If you are interested in buying some cheap files go to harborfreight.com They should have what you are looking for (arched and semi-circle) and it will only cost a couple of bucks ($5-10) for a pack of like four different ones. Hope that helps you out. If you follow One-Up's sketch it should turn out pretty nice.

Looks like a good start to your project! I like battlechaser's idea of adding the spike to your primary cut. Here is pretty much my interpretation of his pic. I rounded off the upper section of the spike, as well as the area behind the feed neck. I think that this will give it a smoother profile.

Also, try and grind down the sides of the body. Make a design on it that will get rid of the stock pilot look (kinda like what I did to make my VS2 not look so much like a VS2). I'll try to think something up and I'll post a pic of what I come up with. Lemme warn you though, I'm not great with photoshop.

What dremel attachments have you been using? To make the spike, I would start by marking your cuts with a sharpie first. Then use the high speed cutting tool that has the ball tip; I found that this was the best tool when trying to make intricate shapes. Once you have the shape that you want, use the drum sander (start with 60 grit) to smooth out the shape of the spike and to make the pointy part pointy. Best advice I can give is this....work slowly. It took me 25+ hours of dremel work to get my halfback the way I wanted it. The time and patience that you put in will reward you in the longrun. One more thing, make sure that you put a slight bevel on the upper tube (advice given to me by Otter). This will ensure that you won't leave any shards that will eat up your bolt.

Damn OneUp, you are too good at this halfback design $#!+....LOL. Forget what I said Omegara, just do whatever OneUp says. I didn't even know that lower tube windows were possible. I tried to say away from the lower tube, but now that I think about it, I can see why it's possible. Too bad I'm sending my body in for anno already cuz I would love to try and incorporate a window into my halfback. Oh well.....but I think you should go for it Omega

Damn OneUp, you are too good at this halfback design $#!+....LOL. Forget what I said Omegara, just do whatever OneUp says. I didn't even know that lower tube windows were possible. I tried to say away from the lower tube, but now that I think about it, I can see why it's possible. Too bad I'm sending my body in for anno already cuz I would love to try and incorporate a window into my halfback. Oh well.....but I think you should go for it Omega

spyders used to be bottom tube cocking, where the cocking knob is attached to the striker, not the bolt, so i think windows were made at the very beginning.

I think as long as the window is aft of the striker oring in cocked position he should be fine.

those are some Awesome ideas, I will give them a shot and keep everyone posted! I just have to figure out how far back the o-ring is in the cocked position so as not to screw it up lol. Thanks for all the ideas and thanks Oneup for the photoshopping...that is a cool skill I wish I had lol.